Max exposure time and reading ISO

Quote from: Dave92F1 on 17 / January / 2021, 15:50:26

Anybody know if there's a way to increase the maximum auto-exposure time in P mode from 1 second? (The camera will do 15 seconds in Tv mode, but not in P mode).

There is not. You can calculate the exposure yourself in script using the camera measured Bv value and the APEX equation

Quote

Also, is there a way to read the ISO chosen by the camera from the JPG file? It seems this field isn't filled out in the EXIF data (altho Picasa shows a "user comment" of 264 bytes - maybe it's in there. Anybody know how to decode the user comment?)

ISO should be recorded in the EXIF, ~~in standard ISO tag~~ and possibly in some of the "maker note" tags. It is not recorded in the user comment. See https://exiftool.org/TagNames/EXIF.html

edit:
Mea culpa, I was wrong about the standard ISO tag. exiftool shows an ISO value, but it's actually a composite value based on makernote tags, as described in this response: https://chdk.setepontos.com/index.php?topic=14218.msg145022#msg145022

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